Thursday, October 30, 2008

Lesson 44: Abandon Ship - Liferafts

Abandon Ship

The decision to abandon ship is usually very difficult. In some instances, people have perished in their life raft while their abandoned vessel managed to stay afloat. Other cases indicate that people waited too long to successfully get clear of a floundering boat.

Once the decision is made:

Put on all available water-proof clothing, including gloves, headgear, and life jacket.

Collect survival kit.

Note present position.

Send out MAYDAY message.

Launch life raft attached to ship.

Launch dinghy attached to life raft.

Try to enter life raft directly from the boat (if impossible, use minimal swimming effort to get on board).

Don't forget the EPIRB (emergency position indicator radio beacon).

Get a safe distance from the sinking vessel.

Collect all available flotsam. The most unlikely articles can be adapted for use under survival conditions.

Use flares only on skipper's orders when there is a real chance of them being seen.Arrange for collecting rainwater. Ration water to maximum one-half quart per person per day, issued in small increments. Do not drink seawater or urine. If water is in short supply, eat only sweets from survival rations.

Lifeboats and Liferafts

A lifeboat is a boat carried on board a ship and designed to allow passengers to escape, or a boat kept on land or in a harbor to rescue people in trouble at sea. Lifeboats are also kept at offshore platforms. As such, it is an elaborate version of a life raft. Lifeboats were historically rigid structures built with highly buoyant materials. More recently however, life rafts are inflatable, equipped with auto-inflation carbon dioxide canisters or mechanical pumps, and split into partitions, so that they are much less subject to the adverse effects of exposure to sea water and sunlight. A quick release and pressure release mechanism is fitted so that the canister or pump automatically inflates the lifeboat, and the lifeboat breaks free of the sinking vessel. The hydrostatic release operates at a depth of about 10 to 12 feet or about 6 psi. Usually the raft over inflates and the pressure relief valve will bleed off the excess pressure. No action is required in this instance. In the event the raft inflates up-side-down, one can right the raft by standing on the CO2 cylinder while using righting straps found on the bottom of the raft. Care should be taken not have the CO2 cylinder strike you on the head as you right the raft. The length of the painter on all USCG approved rafts is 100-feet. The painter should not be cut unless the raft is threatened by either fire or sinking. If left uncut, the paint will keep the raft at its last reported position.